Impact tool



April 13, 1954 G. E. HUGHES IMPACT TOOL Filed Jan. 3, 1950 George Hug/les n INVENTOR.

BY @ab 'f-f M ATTORNEYS yPatented Apr. 13, 1954 UNITED STATES PATENT OFFICE IMPACT TOOL George E. Hughes, SanDiego, Calif.

Application January 3, 1950, Serial No. 136,631

1 Claim. l

This invention relates to new and' useful improvements in hand tools of the type in which impact force is obtained by the reactive force of a contractile member.

The improvements apply to hand tools of the impact type such as usedfor punching, gouging, nail setting, chiseling, tooling leather and analogous operations.

One of the objects of my invention is to provide coaxial enclosing guard sleeves for the contractile coiled impact member.

Another object of my invention is to use these guard sleeves to prevent the impact member from becoming axially or otherwise misaligned when a pulling force is applied and released in the operation of the tool.

A further object of my invention is to provide cooperating stop elements in these guard sleeves which will prevent the extension of the impact member` from exceeding its elastic limit which if it occurred would destroy the usefulness of the impact member.

A still further object of my invention is to provide a total enclosure for the impact coiled member so as to prevent foreign particles and portions of the operators body or clothing from being caught and pinched between the adjacent convolutions of the coiled impact member.

Still further objects and the entire scope of applicability of the present invention will become k `apparent from the detailedy description given hereinafter; it should be understood, however, that the detailed description and speciiic examples are given by way of illustration only and,

While indicating preferred embodiments of the invention, are not given by Way of limitation, said variousv changes and modifications within the spirit and scope of the invention will become apparent to thoseV skilled in the art from this` detailed description.

In the drawings, Figure 1 is an elevation of the tool embodying my invention;

Figure 2 is a sectional elevation of the tool shown in Figure 1;

Figure 3 is an elevation of a type of an interchangeable bit or point for use with the tool; and

Figure 4 is an elevation of another form of bit or point which may be used with the tool.

In the drawings and description like characters refer to similar parts throughout.

A tool carrying member generally indicated at It has a frustro-conical end portion II which is apertured and threaded at I?. to receive a bit or point generally indicated at I3 which is pro- 2. vided with a threaded shank M. Tool carrying member lil is of cylindrical shape at I5 adjacent the upper end of the frustro-conical portion Il and has a knurled surface thereabout as indicated at IS. Next adjacent the upper end of cylindrical portion I5 is a somewhat reduced shank i'l which is threaded as indicated at I3 while still another further reduced shank portion i@ threaded at 2B, terminates the upper end of tool carrying member Ill.

An impact member is generally indicated at 2i and is in. the form of a coiled element having convolutions '22 which at their lower end are threadedly received by the threads 2D on the smaller shank portion |91 thusv connecting the impact member with the tool carrying member IIJ.

A rst coaxial guard sleeve 23 interiorly threaded at its lower end at 23 is telescopically mounted within a second coaxial guard sleeve 24 which is provided with an inturned flange 25' at its lower end thereby forming a stop with anoutturned flange" 26 fabricated on the upper end of sleeve 23 to limit the telescopic movement of sleeve 24 with respect to sleeve 23, the purpose 4of which will presently be described. Sleeve 23 with its telescopic sleeve 24 mounted is slipped over the coiled impact member 2i and its threaded lower end 23 is received by the threads I8 on threaded shank I'l thereby connecting it to the tool carrying member It.

An end member generally indicated at 21 and of a globular shape isprovided with a shank portion 2e threaded atl 29.. This shank portion 28 has an interior coaxial aperture 30 which is threaded as indicated` at 3l. Threadedly engaged in aperture 38 of en'd member 2l is a threaded screw or pin 32 rwhich has its exposed end threadedly received in the end ccnvolutions oi.'

' coiled impact member 2 I whereby the end member 21 is connected to the impact member 2LI. The threads 2Q of shank portion 28 on end member 2l are threadedly received by the interiorly threaded upper end 33 of the second or outer coaxial guard sleeve 24 whereby the end member 2'! interconnects the sleeve 24 with. the impact member 2|.

In Figure l, the sleeve 24 is shown knurled on its surface at its upper end as indicated at 34 and the inner sleeve 23 is provided with a; knurled surface at its lower end 35` which surfaces provide grasping portions for the fingers of the two hands of the operator of the tool.

In Figure 2, the bit or point I3 is shown as being provided with a knurled surface I3 which` permits it to be grasped by the fingers and tightly screwed into the tool carrying member Ii). Bit I3 is depicted as having an extreme taper and a sharp pointed end.

In Figures 3 and 4 there are shown respectively bits or points 35 and 31. Bit 36 has a small flat working point 36 and bit 31 has a secondary tapered point or working surface 31. Each of the bits 36 and 3'I are provided with threaded shanks i4 and knurled finger grasping surfaces similar to bit I3.

In operation of the impact tool according to this invention, the assembled tool as shown in Figures 1 and 2 is grasped at 35 on the sleeve 23 by the fingers of one hand and at 34 on sleeve 24 by the iingers of the other hand of the operator. The end of the bit I3 is placed and held against the work to receive for example a punch hole. Sleeve 24 is pulled axially upward to the amount desired as limited by the cooperating flanges 25 and 2S to tension the coiled impact member 2| and then the grasp at 34 is removed so as to release the impact member. The coming together of the adjacent convolutions of the coiled impact member 2i causes an impinging force in the form of a downward impact to be applied to the tool carrying member IB and in turn the tool rcarried thereby which exerts a prick or punch A hole in the work adjacent Where it is held.

The cooperating flanges 25 and 26 on the coaxial guard sleeves serve to limit the extent of tensioning of the coiled impact member and thus for a given impact member prevents it being tensioned in excess of its ability to properly snap back to its original position of rest without destroying its elastic limit.

The coaxial guard sleeves being telescopic in associated operation and containing the impact member prevent it trom disalignment and allow the fulleiect of its tensioning along its longitudinal axis.

In the operation of this impact tool the sleeves 23 and 24 totally enclose the coiled impact member and prevent foreign particles from interfering with the full operation of the convolutions or points than illustrated herein may be used f with this tool. f

The tool according to this invention has been found particularly useful for working wood, metal, plastic, and leather and for such operations as punching, stamping, gouging, riveting, hammering, calking, embossing, lettering, num bering, and nail setting. l

I claim as my invention:

An impact tool, including a tool carrying member having a rst and a second threaded shank portion; an impact member in the form of a uniformly coiled element having its convolutions normally in close contact with one another, one end of said impact member being threadedly engaged with the second threaded shank portion of said tool carrying member whereby the tool receives'the impact resulting from the striking action of the convolutions against one another when the member is tensioned and released; a rst coaxial guard sleeve surrounding a portion of said impact member and interiorly threaded at one end to thereby threadedly engage with said rst threaded shank portion of said tool carrying member and having an outwardly extending ilange at the other end; a second coaxial guard sleeve with an inturned flange at one end and interiorly threaded at its other end, surrounding the remaining portion of said impact member, and having telescopic engagement with said rst sleeve; said flanges on the guard sleeves each having sliding t with the other sleeve, cooperating to limit the telescopic movement of the sleeves in one direction, maintaining said sleeves in axial alignment and limiting the tensioning of said impact member; an end member having a threaded shank and a threaded aperture in coaxial alignment with the shank; and a threaded member threadedly engaging the other end of said impact member and threadedly engaged in said threaded aperture of the end member thereby connecting said impact member to said end member; said threaded end of the second coaxial sleeve threadedly engaged with said threaded shank on said end member, whereby a pulling force applied and released on said second coaxial member or end member when said tool engaging member is held stationary respectively tensions and releases said impact member to apply an impact on said tool carrying member, said telescopio coaxial guard sleeves totally enclosing said impact member and preventing axial disalignment of said impact member when it is tensioned and released.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 54,852 Burnham May 22, 1866 426,094 Arnold Apr. 22, 1890 802,247 Traxel Oct. 17, 1905 1,250,153 Ellis Dec. 18, 191'? 1,458,961 Williams June 19,A 1923 1,887,085 Ehrlich Nov. 8, 1932 FOREIGN PATENTS Number Country Date 716,433 France Dec. 21, 1931 

